Catheter with tapered self-introducing low-recirculation distal tip

Abstract

Disclosed is a multi-lumen catheter having a distal end catheter tip configured to improve fluid flow into and out from the catheter tip while reducing undesired recirculation during hemodialysis treatment of a patient. A first lumen and a second lumen each extends from the catheter proximal end to the catheter distal end, the first lumen and the second lumen being parallel to each other. A septum having a first side and a second side separates the first lumen from the second lumen. Some embodiments of the catheter tip include a beveled shape region, having a first lumen orifice, a second lumen orifice, and a septum top surface. Within the beveled shape region, at least a portion of the septum first side and at least a portion of the septum top surface form a first eave over the first lumen and at least a portion of the septum second side and at least a portion of the septum top surface form a second eave over the second lumen.

What is claimed: 
     
       1. A low recirculation multi-lumen catheter, comprising:
 an elongated catheter body comprising a catheter top, a catheter bottom, a catheter first side, and a catheter second side; 
 a proximal end; 
 a distal end having a catheter tip; 
 a first lumen extending from the catheter proximal end to the catheter distal end and a second lumen extending from the catheter proximal end to the catheter distal end, wherein the first lumen is substantially parallel to the second lumen; 
 a septum comprising a septum first side adjacent the first lumen and a septum second side adjacent the second lumen, wherein the septum separates the first lumen from the second lumen; 
 a central longitudinal axis extending from the catheter proximal end to the catheter distal end; 
 a central longitudinal plane comprising the central longitudinal axis and extending from the catheter top to the catheter bottom; and 
 a beveled shape region, having bilateral symmetry along the central longitudinal plane, comprising a first lumen orifice, a second lumen orifice, at least a portion of the septum first side, at least a portion of the septum second side, and a septum top surface; wherein
 the first lumen orifices and second lumen orifices locate entirely within the beveled shape region, 
 the first lumen orifices and second lumen orifices having generally ovate shape; 
 at least a portion of the septum first side and at least a portion of the septum top surface form a first eave over the first lumen; and 
 at least a portion of the septum second side and at least a portion of the septum top surface form a second eave over the second lumen; 
 the first eave and the second eave extends to at least half of the septum top surface; 
 the first eave is configured to act as a baffle, when the first lumen is used to introduce fluid, to direct fluid flow out from the first lumen via the first lumen orifice, while restricting cross-over fluid flow to the second lumen; 
 the second eave is configured to act as a baffle, when the second lumen is used to introduce fluid, to direct fluid flow out from the second lumen via the second lumen orifice, while restricting cross-over fluid flow to the first lumen; and 
 the first eave comprises a region of the septum first side leading up into the septum top surface and a half of the septum top surface spanning from the central longitudinal plane to the first lumen orifice, the first eave have an arched shape that forms at least a portion of the first lumen orifice; and 
 the second eave comprises a region of the septum second side leading up into the septum top surface and a half of the septum top surface spanning from the central longitudinal plane to the second lumen orifice, the second eave have an arched shape that forms at least a portion of the second lumen orifice. 
 
 
     
     
       2. The multi-lumen catheter of  claim 1 , comprising:
 a central latitudinal plane comprising the central longitudinal axis and extending from the catheter first side to the catheter second side; 
 an upper latitudinal plane parallel to the central latitudinal plane and bisecting the septum top surface at the top of the first lumen orifice and at the top of the second lumen orifice; 
 a central latitudinal axis extending along the central latitudinal plane and bisecting the septum top surface; and 
 an upper latitudinal axis extending along the upper latitudinal plane and bisecting the septum top surface. 
 
     
     
       3. The multi-lumen catheter of  claim 1 , wherein
 the first lumen can be a dedicated suction line or a dedicated return line; and 
 the second lumen can be a dedicated suction line or a dedicated return line. 
 
     
     
       4. The multi-lumen catheter of  claim 2 , wherein the catheter body comprises
 a generally oval or stadium shaped cross-section; 
 a height, H 1 , measured along the central longitudinal axis and extending from the catheter bottom to the catheter top; and 
 a width, W 3 , measured along the central latitudinal axis and extending from the catheter first side to the catheter second side; 
 wherein H 1  is less than W 3 . 
 
     
     
       5. The multi-lumen catheter of  claim 2 , wherein the septum comprises
 a width, W 1 , measured along the central latitudinal axis and extending from the septum first side to the septum second side; and 
 a width, W 2 , measured along the upper latitudinal axis and extending from the septum first side to the septum second side, 
 wherein W 1  is less than W 2 . 
 
     
     
       6. The multi-lumen catheter of  claim 2 , wherein the beveled shape region comprises a chamfered edge at the distal end of the catheter, the chamfered edge having a thickness, Th 1 , measured along the central longitudinal plane. 
     
     
       7. The multi-lumen catheter of  claim 1 , wherein the beveled shape region comprises a bevel top edge at a proximal end of the beveled shape region and adjacent the catheter top, wherein the bevel top edge can be straight or curved. 
     
     
       8. The multi-lumen catheter of  claim 2 , wherein the septum comprises:
 a septum first segment extending along the septum top surface from the catheter distal end for a distance, D 1 , to the central latitudinal axis; and 
 a septum second segment extending along the septum top surface from the central latitudinal axis for a distance, D 2 , to the upper latitudinal axis. 
 
     
     
       9. The multi-lumen catheter of  claim 6 , wherein the beveled shape region extends for a distance, D 3 , measured parallel to the central latitudinal plane, from the chamfered edge at the catheter distal end to a z-axis;
 wherein the z-axis is perpendicular to the central latitudinal plane, tangential to the bevel top edge, and extends from the catheter top to the catheter bottom. 
 
     
     
       10. The multi-lumen catheter of  claim 2 , wherein the catheter body has a thickness, Th 2 , and a thickness Th 3 , wherein
 Th 2  is measured along the central longitudinal plane and extends from the catheter bottom to the central latitudinal plane; and 
 Th 3  is measured along the central longitudinal plane and extends from the catheter bottom to the upper latitudinal plane. 
 
     
     
       11. The multi-lumen catheter of  claim 1 , wherein the catheter body comprises at least one aperture extending through the catheter top and into at least one of the first lumen and the second lumen. 
     
     
       12. The multi-lumen catheter of  claim 1 , wherein the catheter body comprises at least one aperture extending through the catheter bottom and into at least one of the first lumen and the second lumen. 
     
     
       13. The multi-lumen catheter of  claim 1 , further comprising a third lumen adjacent the first lumen and adjacent the second lumen. 
     
     
       14. The multi-lumen catheter of  claim 2 , wherein the beveled shape region comprises
 a first sidewall forming an outer portion of the first lumen; and 
 a second sidewall forming an outer portion of the second lumen; 
 wherein a first lateral plane tangential to the first sidewall and normal to the central latitudinal plane is offset from the central longitudinal plane by an angle, A 1 ; and 
 a second lateral plane tangential to the second sidewall and normal to the central latitudinal plane is offset from the central longitudinal plane by an angle, A 2 . 
 
     
     
       15. The multi-lumen catheter of  claim 1 , wherein the beveled shape region comprises
 a first lumen orifice cross-section of the first lumen orifice, wherein the first lumen orifice cross-section can have a generally ovate shape, a generally oblong shape, or a generally tear-drop shape; and 
 a second lumen orifice cross-section of the second lumen orifice, wherein the second lumen orifice cross-section can have a generally ovate shape, a generally oblong shape, or a generally tear-drop shape. 
 
     
     
       16. The multi-lumen catheter of  claim 15 , wherein the first lumen orifice cross-section has a generally ovate shape with a first major axis and a first minor axis and the second lumen orifice cross-section has a generally ovate shape with a second major axis and a second minor axis. 
     
     
       17. The multi-lumen catheter of  claim 2 , wherein the beveled shape region comprises at least one plane of symmetry, wherein the plane of symmetry is the central longitudinal plane. 
     
     
       18. The multi-lumen catheter of  claim 1 , wherein the catheter is configured to improve fluid flow into and out from the catheter tip and to reduce undesired recirculation during hemodialysis treatment of a patient.